<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with the
Invariant Sections being "Funding Free Software", the Front-Cover
Texts being (a) (see below), and with the Back-Cover Texts being (b)
(see below).  A copy of the license is included in the section entitled
"GNU Free Documentation License".

(a) The FSF's Front-Cover Text is:

A GNU Manual

(b) The FSF's Back-Cover Text is:

You have freedom to copy and modify this GNU Manual, like GNU
     software.  Copies published by the Free Software Foundation raise
     funds for GNU development. -->
<!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Examples (GNU Compiler Collection (GCC) Internals)</title>

<meta name="description" content="Examples (GNU Compiler Collection (GCC) Internals)">
<meta name="keywords" content="Examples (GNU Compiler Collection (GCC) Internals)">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
<link href="index.html#Top" rel="start" title="Top">
<link href="Option-Index.html#Option-Index" rel="index" title="Option Index">
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
<link href="Mode-Iterators.html#Mode-Iterators" rel="up" title="Mode Iterators">
<link href="Code-Iterators.html#Code-Iterators" rel="next" title="Code Iterators">
<link href="Substitutions.html#Substitutions" rel="prev" title="Substitutions">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
blockquote.smallquotation {font-size: smaller}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
div.lisp {margin-left: 3.2em}
div.smalldisplay {margin-left: 3.2em}
div.smallexample {margin-left: 3.2em}
div.smalllisp {margin-left: 3.2em}
kbd {font-style: oblique}
pre.display {font-family: inherit}
pre.format {font-family: inherit}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
pre.smalldisplay {font-family: inherit; font-size: smaller}
pre.smallexample {font-size: smaller}
pre.smallformat {font-family: inherit; font-size: smaller}
pre.smalllisp {font-size: smaller}
span.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
ul.no-bullet {list-style: none}
-->
</style>


</head>

<body lang="en">
<a name="Examples"></a>
<div class="header">
<p>
Previous: <a href="Substitutions.html#Substitutions" accesskey="p" rel="prev">Substitutions</a>, Up: <a href="Mode-Iterators.html#Mode-Iterators" accesskey="u" rel="up">Mode Iterators</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<a name="Mode-Iterator-Examples"></a>
<h4 class="subsubsection">17.23.1.3 Mode Iterator Examples</h4>

<p>Here is an example from the MIPS port.  It defines the following
modes and attributes (among others):
</p>
<div class="smallexample">
<pre class="smallexample">(define_mode_iterator GPR [SI (DI &quot;TARGET_64BIT&quot;)])
(define_mode_attr d [(SI &quot;&quot;) (DI &quot;d&quot;)])
</pre></div>

<p>and uses the following template to define both <code>subsi3</code>
and <code>subdi3</code>:
</p>
<div class="smallexample">
<pre class="smallexample">(define_insn &quot;sub&lt;mode&gt;3&quot;
  [(set (match_operand:GPR 0 &quot;register_operand&quot; &quot;=d&quot;)
        (minus:GPR (match_operand:GPR 1 &quot;register_operand&quot; &quot;d&quot;)
                   (match_operand:GPR 2 &quot;register_operand&quot; &quot;d&quot;)))]
  &quot;&quot;
  &quot;&lt;d&gt;subu\t%0,%1,%2&quot;
  [(set_attr &quot;type&quot; &quot;arith&quot;)
   (set_attr &quot;mode&quot; &quot;&lt;MODE&gt;&quot;)])
</pre></div>

<p>This is exactly equivalent to:
</p>
<div class="smallexample">
<pre class="smallexample">(define_insn &quot;subsi3&quot;
  [(set (match_operand:SI 0 &quot;register_operand&quot; &quot;=d&quot;)
        (minus:SI (match_operand:SI 1 &quot;register_operand&quot; &quot;d&quot;)
                  (match_operand:SI 2 &quot;register_operand&quot; &quot;d&quot;)))]
  &quot;&quot;
  &quot;subu\t%0,%1,%2&quot;
  [(set_attr &quot;type&quot; &quot;arith&quot;)
   (set_attr &quot;mode&quot; &quot;SI&quot;)])

(define_insn &quot;subdi3&quot;
  [(set (match_operand:DI 0 &quot;register_operand&quot; &quot;=d&quot;)
        (minus:DI (match_operand:DI 1 &quot;register_operand&quot; &quot;d&quot;)
                  (match_operand:DI 2 &quot;register_operand&quot; &quot;d&quot;)))]
  &quot;TARGET_64BIT&quot;
  &quot;dsubu\t%0,%1,%2&quot;
  [(set_attr &quot;type&quot; &quot;arith&quot;)
   (set_attr &quot;mode&quot; &quot;DI&quot;)])
</pre></div>




</body>
</html>
